Installing Espar/Eberspacher Airtronic diesel *AIR* heater

[daveola]

I've decided to install an Airtronic D2 diesel air heater from Espar/Eberspacher into my MCI 102A3.

I have *just* the heater and fuel pump right now, so I'm set with a few questions and was hoping to find people familiar with these or who have actually installed them!

Right now I am mostly trying to figure out the easiest way to wire and mount the device.

1) I don't have the controller and actually want to control it directly from my own thermostat system (which is fantastic and I'll do a writeup about that later).  I am trying to figure out how the wiring works since the install docs only talk about connecting an Espar controller - can I just give it power on the power supply and then switch the "switch-on signal" to 24V to run the heater?  I know it has a built in thermostat as well that I was hoping to just bypass, and one of the wires (grrt) is "Nominal temp" - do I have to give the heater a nominal temp to run at or can I just ignore this?

2) Fuel pump installation supposedly needs to be below the bottom of the heater, but I was hoping to mount the heater directly on the bay floor.  That would put the fuel pump under the floor which seems ghetto and likely to end up destroying the fuel pump (though I suppose I could enclose it).  Not to mention it seems to leave me with an increased probability of fuel gelling.  Any ideas on where to mount such things?  I saw a VW install that had the fuel pump mounted on a bracket on the exhaust, presumably for preheating, but the manual says to not do this - and that seems like a choice likely to destroy a fuel pump or worse.

3) I need to put in air ducts, though my bus already has air ducts!  Anyone ever try connecting the air output directly to any of the ducts, perhaps past the radiator?  Would be nice to not have to add any ducting to the bus if possible.

[daveola]

Oh - and does anyone know if the connector that comes with the heater and/or the fuel pump is any sort of standard?

EDIT:  I believe I've found it, they are "Junior Power Timer" connectors, so it looks like I need a 2-way and 16-way female housing and then the metal crimps that go with it...

Or I might (for now, at least) just use some female disconnects pushed directly onto the flat pins I am accessing.

[Jim Eh.]

Doesn't the original connector have to be in place for diagnostic lead to be plugged in line?

[daveola]

Doesn't the original connector have to be in place for diagnostic lead to be plugged in line?

It does - another reason to keep the original connector.  Which I might have found now, I think it might be a "Junior Power Timer" 929504-6 connector.

Regardless, I am getting suspicious that this *requires* a controller, since I don't know yet how the heater powers the fuel pump, and I also realized that the fan speed is controlled by temperature sensors, so it's not just an on/off control.  I'm betting that the "nominal temp" is just a resistive setting, like a 5k potentiometer or some such, I might have to buy the simplest controller to reverse engineer it so I can use my own control system.

[daveola]

On the good-news side of things, I found a repair manual and it talks about the mini-controller as a "rheostat switch" which is what it looks like, so I'm betting that my 5k pot idea is correct.  I think I might buy one of the mini controllers and test it and then sell it.

Although if someone has one and wanted to measure the output wires, then I would be grateful and would owe you a beer.  

I'd love to know the following:

With the mini-controller disconnected and the button for heat on, what is the resistance across the grey/red and brown/white wires with the temp turned all the way up and also turned all the way down (and finally what does it read with the button for heat off, I'm betting it reads disconnected)